There is multiple way to solve the error if image/images fails to load. The easiest solution is to show to a show a default error image. A line of Javascript can easily handle the error!
Inside you image tag just write the following line of code:
onerror="if (this.src != 'source-of-your-error-image.jpg') this.src = 'source-of-your-error-image.jpg';"
That’s all!